diff options
| -rw-r--r-- | drivers/mmc/host/sdhci.c | 81 | ||||
| -rw-r--r-- | drivers/mmc/host/sdhci.h | 3 | ||||
| -rw-r--r-- | include/linux/mmc/sdhci.h | 1 |
3 files changed, 70 insertions, 15 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index a1ab22415883..07cca557c4b5 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1013,8 +1013,8 @@ static void sdhci_finish_command(struct sdhci_host *host) static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock) { - int div; - u16 clk; + int div = 0; /* Initialized for compiler warning */ + u16 clk = 0; unsigned long timeout; if (clock == host->clock) @@ -1032,14 +1032,45 @@ static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock) goto out; if (host->version >= SDHCI_SPEC_300) { - /* Version 3.00 divisors must be a multiple of 2. */ - if (host->max_clk <= clock) - div = 1; - else { - for (div = 2; div < SDHCI_MAX_DIV_SPEC_300; div += 2) { - if ((host->max_clk / div) <= clock) - break; + /* + * Check if the Host Controller supports Programmable Clock + * Mode. + */ + if (host->clk_mul) { + u16 ctrl; + + /* + * We need to figure out whether the Host Driver needs + * to select Programmable Clock Mode, or the value can + * be set automatically by the Host Controller based on + * the Preset Value registers. + */ + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); + if (!(ctrl & SDHCI_CTRL_PRESET_VAL_ENABLE)) { + for (div = 1; div <= 1024; div++) { + if (((host->max_clk * host->clk_mul) / + div) <= clock) + break; + } + /* + * Set Programmable Clock Mode in the Clock + * Control register. + */ + clk = SDHCI_PROG_CLOCK_MODE; + div--; + } + } else { + /* Version 3.00 divisors must be a multiple of 2. */ + if (host->max_clk <= clock) + div = 1; + else { + for (div = 2; div < SDHCI_MAX_DIV_SPEC_300; + div += 2) { + if ((host->max_clk / div) <= clock) + break; + } } + div >>= 1; } } else { /* Version 2.00 divisors must be a power of 2. */ @@ -1047,10 +1078,10 @@ static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock) if ((host->max_clk / div) <= clock) break; } + div >>= 1; } - div >>= 1; - clk = (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT; + clk |= (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT; clk |= ((div & SDHCI_DIV_HI_MASK) >> SDHCI_DIV_MASK_LEN) << SDHCI_DIVIDER_HI_SHIFT; clk |= SDHCI_CLOCK_INT_EN; @@ -2308,17 +2339,37 @@ int sdhci_add_host(struct sdhci_host *host) host->timeout_clk *= 1000; /* + * In case of Host Controller v3.00, find out whether clock + * multiplier is supported. + */ + host->clk_mul = (caps[1] & SDHCI_CLOCK_MUL_MASK) >> + SDHCI_CLOCK_MUL_SHIFT; + + /* + * In case the value in Clock Multiplier is 0, then programmable + * clock mode is not supported, otherwise the actual clock + * multiplier is one more than the value of Clock Multiplier + * in the Capabilities Register. + */ + if (host->clk_mul) + host->clk_mul += 1; + + /* * Set host parameters. */ mmc->ops = &sdhci_ops; + mmc->f_max = host->max_clk; if (host->ops->get_min_clock) mmc->f_min = host->ops->get_min_clock(host); - else if (host->version >= SDHCI_SPEC_300) - mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_300; - else + else if (host->version >= SDHCI_SPEC_300) { + if (host->clk_mul) { + mmc->f_min = (host->max_clk * host->clk_mul) / 1024; + mmc->f_max = host->max_clk * host->clk_mul; + } else + mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_300; + } else mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_200; - mmc->f_max = host->max_clk; mmc->caps |= MMC_CAP_SDIO_IRQ | MMC_CAP_ERASE; /* diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index e62367491eee..6b0a0ee9ac6e 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -101,6 +101,7 @@ #define SDHCI_DIV_MASK 0xFF #define SDHCI_DIV_MASK_LEN 8 #define SDHCI_DIV_HI_MASK 0x300 +#define SDHCI_PROG_CLOCK_MODE 0x0020 #define SDHCI_CLOCK_CARD_EN 0x0004 #define SDHCI_CLOCK_INT_STABLE 0x0002 #define SDHCI_CLOCK_INT_EN 0x0001 @@ -191,6 +192,8 @@ #define SDHCI_DRIVER_TYPE_C 0x00000020 #define SDHCI_DRIVER_TYPE_D 0x00000040 #define SDHCI_USE_SDR50_TUNING 0x00002000 +#define SDHCI_CLOCK_MUL_MASK 0x00FF0000 +#define SDHCI_CLOCK_MUL_SHIFT 16 #define SDHCI_CAPABILITIES_1 0x44 diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h index b74c8530e959..a88a799ed7c3 100644 --- a/include/linux/mmc/sdhci.h +++ b/include/linux/mmc/sdhci.h @@ -117,6 +117,7 @@ struct sdhci_host { unsigned int max_clk; /* Max possible freq (MHz) */ unsigned int timeout_clk; /* Timeout freq (KHz) */ + unsigned int clk_mul; /* Clock Muliplier value */ unsigned int clock; /* Current clock (MHz) */ u8 pwr; /* Current voltage */ |
